Magnitude 7.8 – 27km SSE of Muisne, Ecuador – April 16, 2016

USGS “The April 16, 2016 M 7.8 earthquake, offshore of the west coast of northern Ecuador, occurred as the result of shallow thrust faulting on or near the plate boundary between the Nazca and Pacific plates. At the location of the earthquake, the Nazca plate subducts eastward beneath the South America plate at a velocity of 61 mm/yr. The location and mechanism of the earthquake are consistent with slip on the primary plate boundary interface, or megathrust, between these two major plates. Subduction along the Ecuador Trench to the west of Ecuador, and the Peru-Chile Trench further south, has led to uplift of the Andes mountain range and has produced some of the largest earthquakes in the world, including the largest earthquake on record, the 1960 M 9.5 earthquake in southern Chile.

While commonly plotted as points on maps, earthquakes of this size are more appropriately described as slip over a larger fault area. Events of the size of the April 16, 2016 earthquake are typically about 160×60 km in size (length x width).

Ecuador has a history of large subduction zone related earthquakes. Seven magnitude 7 or greater earthquakes have occurred within 250 km of this event since 1900.”